Then-Secretary of State Hillary Clinton and Vice President Biden at a White House event in October 2011. A new book says President Obama's aides were then studying whether to replace Biden with the former first lady on the 2012 ticket.
Kevin Dietsch /UPI /Landov
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Vice President Joe Biden leads the first meeting of the working group to explore solutions following the Newtown shooting with Philadelphia Police Commissioner Charles Ramsey and other law enforcement leaders on Dec. 20.
Chip Somodevilla/Getty Images
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